1) Field on the Invention
The present invention relates to a polycarbonate resin with excellent molding. The polycarbonate resin is suitably applicable to uses such as medical instrument parts, table wares, cooking wares and uses such as optical recording media including optical discs, compact discs, laser discs, optical cards, MO discs and digital video discs, electrophotography, spectacle lenses, toys etc.
2) Prior Art
A polycarbonate resin (bisphenol A type polycarbonate resin) obtainable by reaction of 2,2-bis(4-hydroxyphenyl)propane with a carbonic acid ester-forming compound is excellent in transparency, heat resistance, mechanical properties and dimension stability and used widely as engineering plastics. Further, in recent years, polycarbonate resins having various bisphenol skeletons other than the bisphenol A type polycarbonate resins have been suggested and applied to binders for electrophotography, optical recording media such as optical discs, heat resistance films, polarizing films, table wares, cooking wares, etc. As the above-mentioned uses, prior polycarbonates with a fluorene skeleton (Japanese Patent Kokai Nos. 6-145317, 6-25398, 6-216078, 6-322094 and 8-134199) exhibited inferior molding since it had a rigid skeleton and prior polycarbonates with a polysiloxane skeleton (Japanese Patent Kokai No.3-79626 and Japanese Patent No.2662310) also did not exhibit sufficient molding. Thus, there was room of improvement of molding.
An object of the present invention is to provide a polycarbonate resin with excellent molding.
As a result of extensive studies to solve the above-mentioned prior art problems, the inventors have found that a polycarbonate resin obtained from a bisphenol compound having a specific fluorene structure and a bisphenol compound having a specific polysiloxane structure possesses good molding, and have accomplished the present invention.
That is, the present invention provides a polycarbonate resin obtained by reaction of a carbonic acid ester-forming compound with bisphenols consisting of 9,9-bis(4-hydroxy-3-methylphenyl)fluorene and a bisphenol compound(s) having a structure represented by the following general formula (A), an intrinsic viscosity of said polycarbonate resin being 0.2 to 2.0 dl/g; 
wherein R1 and R2 are, each independently, hydrogen, fluorine, chlorine, bromine, iodine, an alkyl group having 1 to 5 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an aralkyl having 7 to 17 carbon atoms, an alkyl group having 1 to 5 carbon atoms with a substituent(s) of an alkyl group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, fluorine, chlorine, bromine or iodine, an aryl group having 6 to 12 carbon atoms with said same substituent(s), an alkenyl group having 2 to 5 carbon atoms with said same substituent(s), an alkoxy group having 1 to 5 carbon atoms with said same substituent(s) or an aralkyl having 7 to 17 carbon atoms with said same substituent(s); R3, R4, R5 and R6 are, each independently, an alkyl group having 1 to 5 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an aralkyl having 7 to 17 carbon atoms, an alkyl group having 1 to 5 carbon atoms with a substituent(s) of an alkyl group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, fluorine, chlorine, bromine or iodine, an aryl group having 6 to 12 carbon atoms with said same substituent(s), an alkenyl group having 2 to 5 carbon atoms with said same substituent(s), an alkoxy group having 1 to 5 carbon atoms with said same substituent(s) or an aralkyl having 7 to 17 carbon atoms with said same substituent(s); R7 is an alkylene group having 1 to 6 carbon atoms, an alkylidene group having 1 to 6 carbon atoms or absent; X is xe2x80x94Si(R8)(R9)Oxe2x80x94, xe2x80x94Si(R10)(R11)Oxe2x80x94, a homopolymer of xe2x80x94Si(R8)(R9)Oxe2x80x94 or xe2x80x94Si(R10)(R11)Oxe2x80x94 having an average polymerization degree of more than 0 and 200 or below or a random copolymer of xe2x80x94Si(R8)(R9)Oxe2x80x94 and xe2x80x94Si(R10)(R11)Oxe2x80x94 having an average polymerization degree of more than 0 and 200 or below; R8, R9, R10 and R11 are, each independently, hydrogen, fluorine, chlorine, bromine, iodine, an alkyl group having 1 to 5 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an aralkyl having 7 to 17 carbon atoms, an alkyl group having 1 to 5 carbon atoms with a substituent(s) of an alkyl group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, fluorine, chlorine, bromine or iodine, an aryl group having 6 to 12 carbon atoms with said same substituent(s), an alkenyl group having 2 to 5 carbon atoms with said same substituent(s), an alkoxy group having 1 to 5 carbon atoms with said same substituent(s) or an aralkyl having 7 to 17 carbon atoms with said same substituent(s).
That is, the present invention is a polycarbonate resin obtained by reacting a carbonic acid ester-forming compound with bisphenols consisting of 9,9-bis(4-hydroxy-3-methylphenyl)fluorene and a bisphenol compound(s) having a structure represented by the general formula (A), an intrinsic viscosity of said polycarbonate resin being 0.2 to 2.0 dl/g; 
wherein R1 and R2 are, each independently, hydrogen, fluorine, chlorine, bromine, iodine, an alkyl group having 1 to 5 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an aralkyl having 7 to 17 carbon atoms, an alkyl group having 1 to 5 carbon atoms with a substituent(s) of an alkyl group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, fluorine, chlorine, bromine or iodine, an aryl group having 6 to 12 carbon atoms with said same substituent(s), an alkenyl group having 2 to 5 carbon atoms with said same substituent(s), an alkoxy group having 1 to 5 carbon atoms with said same substituent(s) or an aralkyl having 7 to 17 carbon atoms with said same substituent(s); R3, R4, R5 and R6 are, each independently, an alkyl group having 1 to 5 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an aralkyl having 7 to 17 carbon atoms, an alkyl group having 1 to 5 carbon atoms with a substituent(s) of an alkyl group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, fluorine, chlorine, bromine or iodine, an aryl group having 6 to 12 carbon atoms with said same substituent(s), an alkenyl group having 2 to 5 carbon atoms with said same substituent(s), an alkoxy group having 1 to 5 carbon atoms with said same substituent(s) or an aralkyl having 7 to 17 carbon atoms with said same substituent(s); R7 is an alkylene group having 1 to 6 carbon atoms, an alkylidene group having 1 to 6 carbon atoms or absent; X is xe2x80x94Si(R8)(R9)Oxe2x80x94, xe2x80x94Si(R10)(R11)Oxe2x80x94, a homopolymer of xe2x80x94Si(R8)(R9)Oxe2x80x94 or xe2x80x94Si(R10)(R11)Oxe2x80x94 having an average polymerization degree of more than 0 and 200 or below or a random copolymer of xe2x80x94Si(R8)(R9)Oxe2x80x94 and xe2x80x94Si(R10)(R11)Oxe2x80x94 having an average polymerization degree of more than 0 and 200 or below R8, R9, R10 and R11 are, each independently, hydrogen, fluorine, chlorine, bromine, iodine, an alkyl group having 1 to 5 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an aralkyl having 7 to 17 carbon atoms, an alkyl group having 1 to 5 carbon atoms with a substituent(s) of an alkyl group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, fluorine, chlorine, bromine or iodine, an aryl group having 6 to 12 carbon atoms with said same substituent(s), an alkenyl group having 2 to 5 carbon atoms with said same substituent(s), an alkoxy group having 1 to 5 carbon atoms with said same substituent(s) or an aralkyl having 7 to 17 carbon atoms with said same substituent(s).
Japanese Patent Kokai (Laid-open) Nos. 6-145317, 6-25398, 6-216078, 6-322094 and 8-134199 disclose that a polycarbonate resin having a fluorene skeleton has hitherto been applied to optical recording media, phase difference films, flat panel displays and lenses by utilizing its optical characteristics. Japanese Patent Kokai (Laid-open) Nos. 6-3838 and 8-134198 disclose that it has been applied to electrophotography and cast films. Further, Japanese Patent Kokai (Laid-open) No. 6-49195 discloses that it has been applied to high heat resistance table wares applicable to a microwave oven.
However, bisphenol having a fluorene skeleton exhibits inferior molding since it has a rigid structure. It was necessary to introduce a soft segment in order to improve molding.
On the other hand, Japanese Patent Kokai (Laid-open) No.3-79626 and Japanese Patent No.2662310 disclose a polycarbonate having a polysiloxane skeleton.
However, since the above-mentioned polycarbonate also did not exhibit sufficent molding, there was room for improvement of molding.
The present invention relates to a polycarbonate resin obtainable by reaction of bisphenols with a carbonic acid ester-forming compound wherein said bisphenols consists of 9,9-bis(4-hydroxy-3-methylphenyl) fluorene (hereinafter, xe2x80x9cBCFLxe2x80x9d) and a bisphenol compound(s) represented by the formula (A) and the amount of the bisphenol compound represented by the formula (A) is 10 to 80% by weight to total amount of the bisphenol compound of the formula (A) and BCFL and the intrinsic viscosity of the polycarbonate thus obtained is 0.2 to 2.0 dl/g.
As the process for producing the polycarbonate resin of the present invention, known processes for producing a polycarbonate resin from bisphenol A and a carbonic acid ester-forming compound, e.g., a process comprising a direct reaction between bisphenol and phosgene (phosgene process) or a process comprising transesterification between bisphenol and a bisaryl carbonate (transesterification process) can be applied.
In the present invention, when the phosgene process is applied, a process comprising reacting excess phosgene with BCFL and then reacting reaction products thus obtained with bisphenol compound of the formula (A) or a process comprising reacting phosgene, BCFL and bisphenol compound of the formula (A) simultaneously may be applied. When the transesterification process is applied, it is preferable to react bisaryl carbonate, BCFL and bisphenol compound of the formula (A) simultaneously.
Among the phosgene process and the transesterfication process, it is preferable to apply the phosgene process, considering reactivity between BCFL and bisphenol compound of the formula (A).
In the phosgene process, the reaction of BCFL, bisphenol compound of the formula (A) and phosgene is performed usually in the presence of an acid bonding agent and a solvent.
Examples of the acid bonding agent include pyridine and alkali metal hydroxides including sodium hydroxide and potassium hydroxide.
Examples of the solvent include methylene chloride, chloroform, chlorobenzene and xylene.
Further, in order to promote polycondensation, catalysts including tertiary amines such as triethylamine and tetraammonium salts are added. In order to adjust polymerization degree, monofunctional compounds including phenol, p-t-butyl phenol and p-cumyl phenol are added as molecular weight modifier. If necessary, a small amount of antioxidants including sodium sulfite and sodium dithionite and a small amount of branching agents including phloroglucine, isatin bisphenol, 1,1,1-tris(4-hydroxyphenyl)ethane and xcex1,xcex1xe2x80x2,xcex1xe2x80x3-tris(4-hydroxyphenyl)-1,3,5-triisopropyl benzene may be added.
The reaction temperature is usually in the range of 0 to 150xc2x0 C. and preferably in the range of 5 to 40xc2x0 C. The reaction time is usually 0.5 minutes to 10 hours and preferably 1 minute to 2 hours, depending on the reaction temperature. It is preferable to maintain pH of the reaction system to 10 or above during the reaction.
In the transesterification process, a mixture of BCFL, bisphenol compound of the formula (A) and bisaryl carbonate is reacted under a reduced pressure at a high temperature. In this reaction, a monofunctional compound(s) including p-t-butyl phenol and p-cumyl phenol may be added as molecular weight modifier.
The reaction is performed usually at a temperature of 150 to 350xc2x0 C. and preferably 200 to 300xc2x0 C. Phenols by-produced by transesterification and derived from bisaryl carbonate are distilled off preferably under a final reduced pressure degree of 1 mmHg or below outside the reaction system. The reaction time is usually about 1 to 6 hours, depending on the reaction temperature or the reduced pressure degree. It is preferable to perform the reaction under the atmosphere of an inert gas such as nitrogen, argon, etc. If necessary, an antioxidant(s) and a branching agent(s) may be added.
Examples of the carbonic acid ester-forming compound include phosgene and bisaryl carbonates such as diphenyl carbonate, di-p-tolyl carbonate, phenyl-p-tolyl carbonate, di-p-chlorophenyl carbonate and dinaphthyl carbonate and a combination of two species of the compounds thereof or above.
Examples of bisphenol compound of the formula (A) include the compounds represented by the below structural formulas and a combination of two species of the compounds thereof or above. 
Among them, at least one compound selected from the group consisting of xcex1,xcfx89-bis[3-(o-hydroxyphenyl)propyl] polydimethylsiloxane, xcex1,xcfx89-bis[2-(p-hydroxyphenyl)ethyl]polydimethlsiloxane, a random copolymer of dimethylsiloxane and methylphenylsiloxane having 3-(o-hydroxyphenyl)propyl group at xcex1 and xcfx89 positions and a random copolymer of dimethylsiloxane and diphenylsiloxane having 3-(o-hydroxyphenyl) propyl group at xcex1 and xcfx89 positions is preferable from the aspect of reactivity.
As the molecular weight modifier which may be used in the present invention, monohydric phenol is preferable. Particularly, it is preferable to use as the molecular weight modifier alkyl phenols having 1 to 4 carbon atoms: alkyl hydroxy benzoate having 1 to 4 carbon atoms and alkyl oxy phenols having 1 to 4 carbon atoms. Among them, phenol and p-t-butyl phenol are preferable.
When the phosgene process is applied to the present invention, it is preferable to react phosgene with BCFL, or BCFL and bisphenol compound of the formula (A) in the presence of a tetraammonium salt in order to perform efficiently the reaction. Examples of tetraammonium salt include tetramethylammonium chloride, trimethylbenzylammonium chloride, triethylbenzylammonium chloride, tetraethylammonium bromide and tetra-n-butylammonium iodide, among which trimethylbenzylammonium chloride and triethylbenzylammonium chloride are preferable. It is preferable that the amount of tetraammonium salt is usually 0.0005 to 5 mol % to total amount of bisphenols to be used.
When the phosgene process is applied, the reactivity is further improved by applying a process comprising reacting excess phosgene with BCFL and then reacting a solution in the state of emulsion thus obtained with bisphenol compound of the formula (A).
The polycarbonate resin thus synthesized can be molded by known molding methods including extrusion molding, injection molding, blow molding, compression molding and wet molding. In order to mold readily and maintain necessary strength, it is preferable that the intrinsic viscosity of the polycarbonate resin is in the range of 0.2 to 2.0 dl/g.
It is preferable that the amount of bisphenol compound of the formula (A) is 10 to 80% by weight to total amount of BCFL and bisphenol compound of the formula (A). When bisphenol compound of the formula (A) is below 10% by weight, effects as soft segment are small and molding and solvent solubility are inferior, whereas above 80% by weight effects as soft segment are too large and the polycarbonate resin is readily changed to a viscous liquid or a rubbery substance.
It is not preferable that impurities unable to remove in the production process are mixed in raw materials of the polycarbonate resin in the present invention. It is preferable to use previously sufficiently purified raw materials.
In order to ensure stability and mold releasing necessary during molding, if necessary, antioxidants such as hindered phenols and phosphates; lubricants and mold releasing agents such as silicones, fatty acid esters, fatty acids and natural fats and oils including bees wax; light stabilizers such as benzotriazoles, benzophenones, dibenzoyl methane and salicylates and antistatic agents such as polyalkylene glycols and fatty acid glycerides may be used together with the polycarbonate resin. Further, a mixture of the polycarbonate resin with resin other than the polycarboante resin may optionally be used within the range not to impair performances.
The present invention will be described in more detail below, referring to Examples, which are not intended to limit the scope of the present invention.
Each properties were measured according to the following methods.
[Intrinsic viscosity [xcex7]]
Intrinsic viscosity [xcex7][dl/g] was measured for a polycarbonate resin solution of 0.5 g/dl concentration in methylene chloride solvent at Huggins""s constant of 0.45 at a temperature of 20xc2x0 C.
[Tensile Test]
18 g of a polycarbonate resin sample was dissolved in 132 g of dichloromethane. A cast film was made from 12 wt/wt % polycarbonate resin solution thus obtained with a spacer of 600 xcexcm and dried. Then, a dumbbell specimen (total length 165 mm, long width 19 mm, short width 13 mm and thickness about 50 xcexcm) according to ASTM D638-84I was punched and prepared.
Tensile test was performed for the dumbbell specimen thus prepared in a room adjusted to 23xc2x0 C. and 50% RH with Tensilon UTM-5, manufactured by Toyo Boldwien k.k., in Japan at a tensile velocity of 50 mm/min., under a load cell of 196N to measure strength and elongation according to ASTM D-882.
[Evaluation of Heat Resistance]
A glass transition temperature and 1% reduced amount starting temperature were measured for a polycarbonate resin powder under the atmosphere of nitrogen with a thermal analyzer (DSC-50, TGA-50H), manufactured by k.k. Shimazu Seisakusho, in Japan. When the glass transition temperature is not clear (appearance of some minute inflection points), the largest inflection point among the inflection points was regarded as a glass transition temperature.
[Evaluation of Appearance of Wet Molded Film]
18 g of a polycarbonate resin sample was dissolved in 132 g of dichloromethane. A 12 wt/wt % polycarbonate resin solution thus obtained was casted with a spacer of 600 xcexcm and dried, thereby obtaining a wet molded film of thickness about 50 xcexcm. Its appearance was evaluated visually.
[Evaluation of Appearance of Compression Molded Article]
A compression molded article (length about 100 mm, width about 100 mm, thickness about 3.2 mm) was prepared from about 50 g of a polycarbonate resin sample with a compression molder S-37, manufactured by k.k. Kamifuji Kinzoku Kogyo, in Japan under compression conditions of 300xc2x0 C. and 9.8 MPa. Its appearance was evaluated visually.
[Birefringence]
The measurement was performed for an injection molded sample of a polycarbonate resin with ARD 130N, manufactured by Oak Co., by a light of 30 degree oblique incidence angle and wave length 632.8 nm.
[Transcription]
The measurement was performed for an injection molded sample of a polycarbonate resin with an atomic force microscope NV2100, manufactured by Olympus Co.
[Photoelastic Sensitivity]
A cast film of thickness 50 xcexcm was prepared from a polycarbonate resin powder sample. The measurement was performed for the cast film with auto-Ellipsometer, manufactured by k.k., Mizojiri Kogaku Kogyo, in Japan under a load of 300 to 1100 g in a wave length of 632.8 nm.